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Toward Closure Of Upwelling Radiance In Coastal Waters, Grace C. Chang, Tommy D. Dickey, Curtis D. Mobley, Emmanuel Boss, W. Scott Pegau
Toward Closure Of Upwelling Radiance In Coastal Waters, Grace C. Chang, Tommy D. Dickey, Curtis D. Mobley, Emmanuel Boss, W. Scott Pegau
Marine Sciences Faculty Scholarship
We present three methods for deriving water-leaving radiance Lw(λ) and remote-sensing reflectance using a hyperspectral tethered spectral radiometer buoy (HyperTSRB), profiled spectroradiometers, and Hydrolight simulations. Average agreement for 53 comparisons between HyperTSRB and spectroradiometric determinations of Lw(λ) was 26%, 13%, and 17% at blue, green, and red wavelengths, respectively. Comparisons of HyperTSRB (and spectroradiometric) Lw(λ) with Hydrolight simulations yielded percent differences of 17% (18%), 17% (18%), and 13% (20%) for blue, green, and red wavelengths, respectively. The differences can be accounted for by uncertainties in model assumptions and model input data (chlorophyll fluorescence quantum efficiency and the spectral chlorophyll-specific absorption …
Subsurface Maxima Of Phytoplankton And Chlorophyll: Steady-State Solutions From A Simple Model, Katja Fennel, Emmanuel Boss
Subsurface Maxima Of Phytoplankton And Chlorophyll: Steady-State Solutions From A Simple Model, Katja Fennel, Emmanuel Boss
Marine Sciences Faculty Scholarship
In oligotrophic lakes and oceans, the deep chlorophyll maximum may form independently of a maximum of phytoplankton biomass, because the ratio of chlorophyll to phytoplankton biomass (in units of carbon) increases with acclimation to reduced light and increased nutrient supply at depth. Optical data (beam attenuation as proxy for phytoplankton biomass and chlorophyll fluorescence and absorption as proxies for chlorophyll concentration) and conventional measurements of biovolume, particulate organic carbon, and chlorophyll from two oligotrophic systems (Crater Lake, Oregon, and Sta. ALOHA in the subtropical North Pacific Ocean) are presented and show a vertical separation of the maxima of biomass and …
The Effect Of Bottom Substrate On Inherent Optical Properties: Evidence Of Biogeochemical Processes, Emmanuel Boss, J. Ronald V. Zaneveld
The Effect Of Bottom Substrate On Inherent Optical Properties: Evidence Of Biogeochemical Processes, Emmanuel Boss, J. Ronald V. Zaneveld
Marine Sciences Faculty Scholarship
Measurements of inherent optical properties (IOP) were conducted over bottoms with different substrates by use of a sampling package mounted on and operated by a SCUBA diver. It was found that in areas of low ambient currents the distribution of IOP varies with bottom type in (1) its value relative to a nearby bottom of different type, (2) its vertical gradient, and (3) its variability. This implies that radiative transfer modeling in shallow environments may need to include, besides the bottom characteristics, the bottom effect on in-water IOP. In tidally flushed shallow banks, vertical and horizontal gradients over scales of …
The Influence Of Bottom Morphology On Reflectance: Theory And Two-Dimensional Geometry Model, J. Ronald V. Zaneveld, Emmanuel Boss
The Influence Of Bottom Morphology On Reflectance: Theory And Two-Dimensional Geometry Model, J. Ronald V. Zaneveld, Emmanuel Boss
Marine Sciences Faculty Scholarship
The reflectance of the bottom is of importance when interpreting optical data in shallow water. Closure studies of radiative transfer, interpretation of laser line scanner data, lidar, and remote sensing in shallow waters require understanding of the bottom reflectance. In the Coastal Benthic Optical Properties experiment (CoBOP), extensive measurements of the material reflectance (reflectance very close to the bottom) were made. Far field reflectance will be needed in carrying out closure of the radiative transfer model and observed radiometric and inherent optical properties. The far field reflectance is the bottom reflectance that includes the effect of bottom morphology (such as …